Calculating-machine



E. B. FREW, CALCULATING MACHINE.

No. 582,634. Patented May 18,1897.

UNITED STATES PATENT OEEIcE,

EUGENE B. FRElV, OF CHICAGO, ILLINOIS.

CALCULATENG-MACHINE,

SPECIFICATION forming part of Letters Patent No. 582,634, dated May 18, 1897'.

Application filed February 6,1897. Serial No. 622,249. (No inodeld To aZZ whom it may concern.-

Be it known that I, EUGENE B. FREW, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Calculating Machines, of which the following is a specification, refer ence being had to the accompanying drawings, which are made a part hereof, and in which Figure 1 is a perspective view of a calculating-machine embodying the invention in its preferred form. Fig. 2 is a perspective view of one of the indicators. Fig. 3 is a section thereof on the line 3 3, Fig. 2. Fig. 4C is a perspective view of the part hereinafter called the carrier and of three indicators of modilied construction in place thereon.

The subject of the present invention is a calculating-machine which is capable of solving problems in addition, subtraction, multi plication, division, and extraction of square and cube root, and while the invention is applicable to machines having this extensive range of usefulness its special object is to provide a simple machine for practical use in multiplying sums together for the purpose of extending invoices and the like, for accurately and quickly ascertaining the interest on any given sum for a stated time, and for other general commercial calculations. a

To these ends the invention consists in the features of novelty that are hereinafter fully described with reference to the drawings aforesaid, in which A represents a table used in making the calculations.

For the purposes of this application I have selected-a multiplication-table, but it will be understood that the character of the table used will depend upon the character of the calculations to be made.

It is the intention that each machine shall be accompanied by a number of tables corresponding in characters with the characters of the calculations to be made and that specially-arranged tables shall be provided for making calculations in special lines of business. I desire to have it understood, therefore, that while this specification will, for the sake of brevity and elearness, be con fined to a n1ultiplication-table and the manner of manipulating the improved calculating-machine in connection therewith, still in its broadestaspect the invention is not limited thereto. In fact, the invention resides principally in the machine itself and is concerned with the character of the table used in connection therewith only to the extent of requiring that it be of such a character as will enable the machine to be used in connection therewith substantially in the manner hereinafter described for making calculations.

The table shown in the drawings has a vertical row or column a of whole numbers ranging from l to 14, inclusive, and a horizontal row a of whole numbers ranging from l to 11, inclusive, but in practice each of these rows of numbers will range from 1 to 100, inclusive.

The range of the table shown in the drawings is sufficient for the purpose of clearly illustrating the manner of using the improved machine, and the table of the full range that will be used in practice is not shown in the drawings for the reason that its scale would have to be objectionably small.

The numbers in the rows a and a will be herein callec m ultiplicands 2L11( multipliers, respectively, but it is obvious that these terms might with equal propriety be interchanged. In addition to the m ultiplican ds and multipliers the table is provided also with whole numbers, representing products, arranged in intersecting vertical and horizontal rows, one of the vertical rows falling beneath each of the multipliers and one of the horizontal rows falling opposite each of the multiplicands in the manner which is customary in multiplication-tables. In addition to the whole numbers the row of multipliers may contain any desired fractions, as shown at a. In the drawings only three fractions are shownto wit, i, and g, but it will be understood that in practice the table will contain those fractions which are of most frequent occurrence in the particular business in which the machine is intended for use. Below these fractional multipliers are figures representing products and arranged in intersecting vertical and horizontal rows, a vertical row falling beneath each of the fractional multipliers and a horizontal row falling opposite each of the multiplicands in the row a.

The table A, of whatever character, is arranged upon a base B. This base preferably takes the form of a box having a drawer l) for containing the tables not in use. Its top side has a sunken panel corresponding in dimensions with the dimensions of the table, and at the corners of this sunken panel are sunken plates 1), beneath which the corners of the table may be inserted for holding it in place upon the base. It is the intention that these tables shall be made of cardboard, celluloid, or some other similar material which will permit of its being bent without injury sufficiently to enable its corners to be inserted beneath the corner-plates in the manner described.

O is a guide-rod which is disposed at one side of the base and extends from end to end thereof, its ends being supported by brackets c, which in turn are secured to the base.

D is a part hereinafter called a carrier. It consists of a metal bar having parallel edges, which is of suflicient length to cross the table from top to bottom and is provided at one of its ends with a lateral perforation for receiving the red 0, upon which it is adapted to slide, its other end being supported by a rib E, which rises from the face of the base. This rib preferably consists of a strip of metal secured to the base either by screws or by being let into the surface thereof.

F F are indicators mounted upon the carrier so as to be capable of sliding thereon independently of each other. These indicators are of similar construction, and hence, for the sake of brevity, in describing their construction this specification will be confined to one of them, similar parts in both being indicated by similar letters of reference.

As shown more clearly in Figs. 2 and 3, the indicator consists of a block f, preferably of metal, through which is an opening f of sufiicient size to freely admit the carrier, and from which projects a finger or pointer f. Through one side of the block is formed an opening f, the outer portion of which is threaded for the reception of corresponding threads on a set screw G, and within this opening is placed a coiled springII, which bears at one end against the edge of the carrier 1) and at the other end against the end of the screw G, on which is a j am-nut I. The spring, having contact with the carrier, acts as a friction-brake which offers suflicient resistance to the movement of the indicator upon the carrier to prevent its accidental displacement, while at the same time permitting it to be freely moved when desired. The object of the screw G is to regulate the tension of the spring, and the object of the nut I is to prevent the screw from backing away when the spring has been adjusted to the proper tension. The upper side of the finger f is in the nature of a straight-edge, and immediately above the plane of this straight-edge the block f is provided with a horizontal row of ciphers and with means for holding in place a slide J, which is adapted to conceal all of said ciphers in any one position, and when drawn away from this position to disclose them successively, proceeding from the left-hand end of the row. As a means for securing this slide in place I prefer to provide the block with an undercut groove and to make the edges of the slide complementary thereto, the right-hand end of the slide being provided with a short lateral projection j, which is adapted to be engaged by the thumb or finger for moving it.

In Fig. l I have shown upon the carrier a row ct of multiplicands, corresponding with the multiplicands in the row a. In Fig. l I have shown a carrier without these multiplieands, and I have shown upon it three indicators,which are without the ciphersf or their accessories and are without friction-brakes.

The manner of manipulating the machine is as follows: Let it be assumed that the slides J are so placed as to conceal all of the ciphers on the indicators. lVhile the slides are in these positions, so far as the solution of the problem is concerned the indicators will not differ from those shown in Fig. t, on which no ciphers are placed, and I will therefore first describe the manner of manipulating the machine shown in Figs. 1, 2, and 3 without reference to these ciphers, or, in other words, I will first describe the manner of 1nanipulat ing a machine which has indicators constructed as shown in Fig. 4, on which the ciphers are not placed. If it be desired to multiply any number in the row of multiplicands by any number in the row of multipliers, only one of the indicators need be used. For example, to multiply 7 by 11 the indicator F is moved upon the carrier until 11 in the row of multiplieands appears immediately above it, and the carrier is then moved until the number 7 in the row of multipliers appears immediately at its left, whereupon the result, 77, may be read immediately above the finger of the indicator.

By the use of a plurality of indicators the machine is made available for multiplying two numbers either or both of which is beyond the range of the table itself.

Suppose, for example, it be required to multiply 1,103 by 7. One of theindicators is used for multiplying the units and tens and the other indicator is used for multiplying hundreds and thousands. That is to say, the indicator F is placed directly beneath 3 and the indicator F is placed directly beneath 11 in the row of mult-iplicands. The carrier is then moved until the multiplier 7 appears immediately at its left. Innuediately above the indicator F the number 21 is read and immediately above the indicator F the number 77 is read; but since this latter indicator is, as we know, being used to multiply hundreds, the power of the multiplicand is raised one-hundredfold, and hence two ciphers must be added to the product indicated, so that instead of reading it as 77 it is read as 7,700. \Vhen the product appearing above the indicator F is added to this, we have, as the result, 7,721. To use the machine in this way necessitates the mental operation of carrying the ciphers, and it is in order to avoid errors which will result from a failure to properly add these ciphers to the product that I prefer to place upon each of the indicators the series of ciphers and the slide J. lVhen these ciphers and the slide are used, whenever the power of the multiplier or the multiplicand is to be raised tenfold one-hundredfold, one-thousandfold, &c., the slide J is so placed as to disclose the proper number of ciphers at the left-hand end of the series. For example, in solving the problem last above given the slide of the indicator F will be so placed as to disclose two ciphers at the left of the series, so that they may be read in connection with the number 77 appearing above the finger of the indicator. Thus the machine gives as the result of the operation 7,700 and 21, leaving only the adding of these numbers together in order to obtain the complete result.

By increasing the number of indicators the machine may in the same manner be used for multiplying numbers containing five or more figures upon a table having multipliers and multiplicands ranging from one to one hundred.

In order to avoid the necessity for moving the carrier to the row CL of multiplicands for the purpose of determining the positions of the indicators at the commencement of each operation, a second row of multiplicands is preferably placed upon the carrier itself.

Having thus described my invention, the following is what I claim as new therein and desire to secure by Letters Patent:

1. I11 a calculating-machine of the class described, the combination with a table having intersecting rows of figures, of a carrier in ovable across the table in one direction and a plurality of indicators mounted upon the carrier and independentlymovable thereon in a direction which is transverse to that in which the carrier is movable, substantially as set forth.

2. In a calculating-machine of the class described, the combination with a table and a carrier movable across the table, of an indicator slidably mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, substantially as set forth.

3. In a calculating-machine of the class described, the combination with a table and a carrier movable across the table in one direction, of an indicator slidably mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, said indicator having a finger projecting laterally from the carrier, substantially as set forth.

4:. In a calculating-machine of the class described, the combination with a table, of a carrier movable across the table and having parallel edges, and an in dicator having an opening through which the carrier passes whereby the indicator is supported by the carrier so as to be slidable thereon in a direction which is transverse to that in which the carrier is movable, substantially as set forth.

5. In a calculating-machine of the class described, the combination with a base, a table supported thereby, and a rod supported by the base, of a carrier having a lateral opening through which the rod passes whereby the carrier is supported by the rod so as to be capable of sliding thereon, and an indicator mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, substantially as set forth.

0. In a calculating-machine, the combina tion of a table, a base having in its top a depression occupied by the table, a carrier, means for supporting it and permitting it to be moved across the table, and an indicator mounted upon the carrier and movable thereon, substantially as set forth.

7. In a calculatirig-machine of the class described, the combination of a table, a base by which it is supported, a rod supported by the base, a carrier slidably mounted upon the red at one end, a bead, supported by the base, upon which the carrier rests near its other end, and an indicator mounted upon the carrier and movable thereon, substantially as set forth.

8. In a calculating-machine of the class described, the combination with a table having intersecting rows of figures, of a carrier movable across the table in one direction, an indicator mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, and a row of ciphers disposed upon the indicator, substantially as set forth.

9. In a calculating-machine of the class described, the combination with a table having intersecting rows of figures, and a carrier movable across the table in one direction, of an indicator mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, a row of ciphers disposed upon the indicator and means for concealing or disclosing the ciphers at will, substantially as set forth.

10. In a calculating-machine of the class described, the combination with a table having intersecting rows of figures, and a carrier movable across the table in one direction, of an indicator mounted upon the carrier and movable thereon in a direction which is transverse to that in which the carrier is movable, a row of ciphers disposed upon the indicator, and a slide mounted upon the indicator and adapted IOO to conceal or disclose the ciphers at will, suhmovable, and a brake carried by the indicator stantially as set forth. and engaging the carrier, substantially as set no 11. In a calculating-inachine of the class deforth.

scribed, the combination with a table and a FUHWF F )FW 5 carrier movable across the table in one direc- T b J tion, of an indicator mounted upon the car- \Vitnesses:

rier and movable thereon in a direction which L. M. .IIOPKINS,

is transverse to that in which the carrier is 1. (moss. 

